package org.jeecg.common.util.encryption;

import org.apache.shiro.codec.Base64;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.util.Objects;

/**
 * AES 加密
 */
public class AesEncryptUtil {
    //使用AES-128-CBC加密模式，key需要为16位,key和iv可以相同！
    private static String KEY = EncryptedString.key;
    private static String IV = EncryptedString.iv;

    /**
     * 加密方法
     *
     * @param data 要加密的数据
     * @param key  加密key
     * @param iv   加密iv
     * @return 加密的结果
     * @throws Exception
     */
    public static String encrypt(String data, String key, String iv) throws Exception {
        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");//"算法/模式/补码方式"NoPadding PkcsPadding
            int blockSize = cipher.getBlockSize();
            byte[] dataBytes = data.getBytes();
            int plaintextLength = dataBytes.length;
            if (plaintextLength % blockSize != 0) {
                plaintextLength = plaintextLength + (blockSize - (plaintextLength % blockSize));
            }
            byte[] plaintext = new byte[plaintextLength];
            System.arraycopy(dataBytes, 0, plaintext, 0, dataBytes.length);
            SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), "AES");
            IvParameterSpec ivspec = new IvParameterSpec(iv.getBytes());
            cipher.init(Cipher.ENCRYPT_MODE, keyspec, ivspec);
            byte[] encrypted = cipher.doFinal(plaintext);
            return Base64.encodeToString(encrypted);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 解密方法
     *
     * @param data 要解密的数据
     * @param key  解密key
     * @param iv   解密iv
     * @return 解密的结果
     * @throws Exception
     */
    public static String desEncrypt(String data, String key, String iv) throws Exception {
        try {
            byte[] encrypted1 = Base64.decode(data);
            Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
            SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), "AES");
            IvParameterSpec ivspec = new IvParameterSpec(iv.getBytes());
            cipher.init(Cipher.DECRYPT_MODE, keyspec, ivspec);
            byte[] original = cipher.doFinal(encrypted1);
            return new String(original);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 使用默认的key和iv加密
     *
     * @param data
     * @return
     * @throws Exception
     */
    public static String encrypt(String data) throws Exception {
        return encrypt(data, KEY, IV);
    }

    /**
     * 使用默认的key和iv解密
     *
     * @param data
     * @return
     * @throws Exception
     */
    public static String desEncrypt(String data) throws Exception {
        return desEncrypt(data, KEY, IV);
    }

    /**
     * 测试
     */
    public static void main(String[] args) throws Exception {
        String test1 = "sa";
        String test = new String(test1.getBytes(), StandardCharsets.UTF_8);
        String data = null;
        String key = KEY;
        String iv = IV;
        // /g2wzfqvMOeazgtsUVbq1kmJawROa6mcRAzwG1/GeJ4=
        data = encrypt(test, key, iv);
        System.out.println("数据：" + test);
        System.out.println("加密：" + data);
        String jiemi = Objects.requireNonNull(desEncrypt(data, key, iv)).trim();
        System.out.println("解密：" + jiemi);
    }
}
